need spud recipe

Good day. I need a recipe for a really good dish of mashed potatoes,
preferably to serve about 50 people.It can contain almost anything, just
so long as it's really good, interesting and can be made the day ahead.
I will make it Thursday evening and serve it Friday evening, reheated in
the oven in a large lasagna pan.
I do a lot of quanitity cooking for a theater group and will need to
cater a party in early April. Is there a website for quantity cooking I
can investigate?
Thanks.
Susan
vloglady@xxxxxxxxx
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